A virtual machine in a virtual computing infrastructure can run on a host device that comprises physical hardware and virtualization software. One or more applications that can run within the virtual machine can generate data that may be stored on one or more virtual disks. Virtual disks can be raw devices. A raw device is a type of block device file that allows accessing a storage device such as a hard disk directly, bypassing operating system caches and buffers. An application can use a raw device directly, enabling the application to manage how data is cached, rather than deferring cache management to the operating system. A raw device can be mapped to one or more portions of storage. A portion of storage can include a logical unit of storage (“LUN”). A portion of storage may be a part of one or more storage appliances. Thus, a virtual disk may span multiple physical storages. A raw disk mapping file enables a virtual machine to view a virtual disk as though it is a single physical disk. A raw disk mapping file maps a virtual disk to portions of storage that make up the raw device. Typically, the raw disk mapping file resides on the storage device that provides the portions of storage that make up the raw disk. The raw disk mapping file for a virtual disk is typically not visible to the virtual machine for which the virtual disk is configured. Raw disk mapping can be either physical mapping or virtual mapping. In virtual mapping, the disk is presented as it if is a logical volume, or a virtual disk file, to a guest operating system and real hardware characteristics of a storage device are hidden. In physical mapping, the Virtual Machine Manager bypasses input/output (I/O) virtualization software and passes I/O commands directly to the physical storage device.
A remote backup server can be used to backup one or more virtual disks of a virtual machine. However, the backup server does not have visibility into the virtual machine to determine the identification of the virtual disks configured for a particular virtual machine. Further, the backup server does not have visibility into the relationship between the virtual machine, the virtual disk(s) configured for the virtual machine, and the raw disk device maps for the virtual disk(s) that would let the backup server backup a virtual disk that comprises a raw device for the virtual machine.